Flexibility is a principal objective in the design of machines and mechanisms. One key advantage is the reduction of costs associated with both the design and manufacture of a mechanism. One technique for achieving a flexible design comprises the standardization of both component parts and whole assemblies in a device. Standardization allows a single device, or slight variations thereof, to be used in a variety of applications thus avoiding expenses in the design and manufacture of a separate mechanism. Standardization also promotes labor savings and reduces the cost of replacement parts while increasing their interchangeability and availability.
In coin receipt mechanisms incorporated in bulk vending machines, for example, a universal design is desirable which can be repeatedly adjusted to accept a selected coin from various possible denominations. The monetary value of each of various coin denominations in a given currency is indicated by the physical size and shape of the coin. In the currency of the United States, for instance, the assorted coin denominations include the penny, nickel, dime, quarter, the fifty cents piece and the dollar. All of these coins are annular in configuration. However, each of these denominations comprises a unique diameter and thickness. Canada employs substantially corresponding denominations but its coins are of different sizes compared to each other and to the currency of the United States. Thus, a coin mechanism design capable of universal adaptation, as for example, to both sets of currencies, is desirable.
Inserting the appropriate coin denomination in the coin mechanism of a bulk vending machine allows a buyer to rotate a crank handle to operate the machine and dispense a product. The product may be a measured amount of a commodity, for instance, candy or discrete containers, e.g. capsules.
As a general rule, vending machine coin receipt mechanisms include one or more discrimination or rejection features. The purpose of these features is to distinguish between coin denominations and allow the mechanism to reject incorrect denominations. This prevents a machine from being cheated by operating upon receipt of a coin of an incorrect denomination of lesser value, or upon receipt of a "slug" (a counterfeit coin comprising a piece of ordinary metal, for example, machined or molded with dimensions near those of a legitimate coin).
The discrimination function may be effected by means of a variety of mechanical devices in a coin receiving mechanism designed to exploit the correspondence between a coin denomination and its physical attributes, e.g. size, shape or thickness. As an example, a slot in a coin receiving mechanism tightly dimensioned, in width or thickness, for accepting dimes would preclude insertion of a penny or nickel. This is because the dime has a smaller diameter and thickness when compared to other coins.
Thus, in a coin-operated machine using a coin-mechanism with discrimination features, the ability to "accept" a particular coin size is determined by the ability of the coin to pass through the discrimination devices. Consequently, coin receiving mechanisms equipped with rejection features inherently tend to preclude universal designs accepting different denominations.
A universal design would afford the advantages of flexibility outlined above. Additionally, there are several more specific reasons, from the perspectives of a vending machine manufacturer and users, that make a universal coin receiving design desirable.
As noted, a universal design would enable a single coin mechanism model to be used in different applications. A single vending machine could use the same model coin mechanism with simple modification to sell separate products at different prices if the coin mechanism was adapted to receive only the corresponding distinct denomination.
Also, when the price of a particular commodity changes, the coin receipt mechanism in a given vending machine could be reconfigured to require coin denominations corresponding to the new price without the need to replace the entire coin mechanism or substantial components thereof. Finally, in employing a given model of coin mechanism in most countries, a universal design would allow adapting the mechanism to the local currency comprising a whole new set of denominations.